1. Field of the Invention
The present invention pertains to a circuit arrangement for flame detection for a transistor coil ignition system of a burner, which features a trigger stage that triggers a power transistor which is located in the power circuit of the primary winding of an ignition coil.
2. Description of Related Art
A transistor coil ignition system, whose structure and operation are known per se, is provided as an ignition device in burners that operate on gas, diesel fuel, gasoline, or other fuels. The desire in this regard is to monitor the burner flame, i.e., to provide for flame detection and ignition diagnosis.
German Published Application 37 06 555 discloses one way of providing an ionization electrode for flame monitoring of an ignition device in the form of a glow plug with a glow-plug body that is integrated into the glow plug. In the case of this known type of flame monitoring, additional circuitry is needed for triggering, whereby ignition diagnosis is still difficult and signal analysis proves to be prone to error. From the standpoint of fabrication engineering, additional design expenses also result.
German Published Application 41 07 335 discloses a process and a device for ignition monitoring of an ignition system. This process and device can be used to check the ignition system for shunts and breaks on the secondary high-voltage side. In addition, ignition diagnosis is performed in the ignition phase.